Read the following article and answer the question. Article: In elementary school, Guadalupe Quintanilla was often referred to as a "slow learner" by her teachers. But she really wasn't slow at all. She just didn't understand the language used in the classroom. Her problem was that she didn't speak English. So she left school after the fourth grade. When Guadalupe grew up, married, and had children of her own, she knew that her children were clever. But some of their teachers didn't think so. The children were having trouble in school because they didn't speak English. Mrs Quintanilla was angry. She didn't want people to think that her children were slow learners. So she decided to learn English herself as a way of helping them. She practiced English. She looked up words in the dictionary. She asked the school headmaster to let her sit in on classes. It wasn't easy, but she passed all her exams. She said that many of the other students helped her. Mrs Quintanilla has helped her children with their lessons. Her two sons have won success. One is a teacher, and the other is a doctor. Her youngest child, a daughter, is studying in a university. Question: According to the story, children who don't speak English _ . Answer:
may have more trouble in school