user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: Where is the beginning of the river that flows through Songo, Mozambique? 
Knowledge Triplets: City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h51_h
City/Town/Village, freebase.type_profile.kind, Significant
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011jt74t
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckjwd
City/Town/Village, freebase.type_profile.strict_included_types, Location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011nbp0r
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011lvjc_
Dated location, freebase.type_profile.strict_included_types, Abstract
City/Town/Village, freebase.type_profile.published, Published
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011tz0b1
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010r12s4
Location, freebase.type_profile.strict_included_types, Inanimate
Postal codes, type.property.schema, City/Town/Village
City/Town/Village, type.type.domain, Location
Dated location, freebase.type_hints.included_types, Location
Dated location, freebase.type_profile.strict_included_types, Location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010rnll5
City/Town/Village, freebase.type_profile.strict_included_types, Inanimate
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckk2n
City/Town/Village, freebase.type_hints.included_types, Location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011c38cw
Dated location, type.type.domain, Location
Significant, freebase.type_kind.types, City/Town/Village
City/Town/Village, base.descriptive_names.names.descriptive_name, m.0105y_05
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckk64
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckjyy
City/Town/Village, freebase.type_hints.included_types, Dated location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckj_k
Location, type.type.domain, Location
Statistical region, freebase.type_profile.strict_included_types, Abstract
City/Town/Village, freebase.type_profile.equivalent_topic, City
City/Town/Village, freebase.type_profile.strict_included_types, Abstract
City Limits, type.property.schema, City/Town/Village
City/Town/Village, freebase.type_profile.strict_included_types, Statistical region
City/Town/Village, base.descriptive_names.names.descriptive_name, m.0111t6vw
City/Town/Village, type.type.properties, Postal codes
Location, freebase.type_hints.included_types, Topic
City/Town/Village, freebase.type_profile.strict_included_types, Dated location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h51x5
Statistical region, freebase.type_profile.published, Published
Statistical region, freebase.type_profile.strict_included_types, Topic
Location, freebase.type_profile.published, Published
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010kkbfd
Dated location, freebase.type_profile.published, Published
Statistical region, type.type.domain, Location
Statistical region, freebase.type_hints.included_types, Location
Statistical region, freebase.type_hints.included_types, Topic
City Limits, rdf-schema#domain, City/Town/Village
City, freebase.equivalent_topic.equivalent_type, City/Town/Village
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011nr3__
City/Town/Village, freebase.type_profile.equivalent_topic, Town
City/Town/Village, base.descriptive_names.names.descriptive_name, m.012w3hyx
Songo, Mozambique, common.topic.notable_types, City/Town/Village
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011vl2ss
City/Town/Village, base.descriptive_names.names.descriptive_name, m.0111t6pl
Statistical region, freebase.type_profile.strict_included_types, Inanimate
Dated location, freebase.type_hints.included_types, Topic
Village, freebase.equivalent_topic.equivalent_type, City/Town/Village
City/Town/Village, freebase.type_profile.equivalent_topic, Village
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010kkbry
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011m57bw
Dated location, freebase.type_profile.strict_included_types, Inanimate
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckjv4
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011x4lp6
Dated location, freebase.type_profile.strict_included_types, Topic
Postal codes, rdf-schema#domain, City/Town/Village
Songo, Mozambique, common.topic.notable_for, g.125h68v6f
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h51zj
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011jt6z3
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010kk9vk
Topic, freebase.type_profile.published, Published
City/Town/Village, freebase.type_hints.included_types, Topic
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h51yy
City/Town/Village, type.type.properties, City Limits
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011f9yg3
City/Town/Village, freebase.type_hints.included_types, Statistical region
City/Town/Village, base.descriptive_names.names.descriptive_name, m.012z3l2r
City/Town/Village, base.descriptive_names.names.descriptive_name, m.012_74vb
City/Town/Village, freebase.type_profile.kind, Definition
City/Town/Village, common.topic.article, m.03bnd2c
City/Town/Village, base.descriptive_names.names.descriptive_name, m.0114s4js
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h5200
City/Town/Village, freebase.type_profile.strict_included_types, Agent
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011m9jg_
Statistical region, freebase.type_profile.strict_included_types, Location
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011jtngz
Town, freebase.equivalent_topic.equivalent_type, City/Town/Village
City/Town/Village, base.descriptive_names.names.descriptive_name, m.011ckkfd
City/Town/Village, base.descriptive_names.names.descriptive_name, m.012_976x
City/Town/Village, freebase.type_profile.strict_included_types, Topic
City/Town/Village, base.descriptive_names.names.descriptive_name, m.010h51y0

Answer: Mwinilunga