user: What is the city of Denver like?

assistant: Denver is a big city, nestled directly to the east of the Rocky Mountains. Many people that live in Denver are educated and have a friendly attitude. It is a family friendly and dog friendly city, with many parks, recreational activities and a lot of green space/trails. With the abundance of green space, and 300 days of sunshine, Denver provides many opportunities to have an active lifestyle. Some of the most popular activities include hiking, biking, rock climbing and skiing.

user: Why are plants green?

assistant: Green coloration comes from the reflection of light off of a plant's cells. The plants cells are full of photosynthesizing chemicals called chlorophyll which reflect a green color. Not all plants look green though, due to the ability to reflect other wavelengths of light. When plants lose chlorophyll they will tend to lose the green color. This is why plants lose their green color in the fall and turn into red, orange, and yellow.

user: how many strings guitar have?
how guitar projects sound?
what are different types of guitar?

assistant: <think>
The guitar is a fretted musical instrument that typically has six strings. It is usually held flat against the player's body and played by strumming or plucking the strings with the dominant hand, while simultaneously pressing selected strings against frets with the fingers of the opposite hand. A plectrum or individual finger picks may also be used to strike the strings. The sound of the guitar is projected either acoustically, by means of a resonant chamber on the instrument, or amplified by an electronic pickup and an amplifier.

The guitar is classified as a chordophone – meaning the sound is produced by a vibrating string stretched between two fixed points. Historically, a guitar was constructed from wood with its strings made of catgut. Steel guitar strings were introduced near the end of the nineteenth century in the United States, nylon strings came in the 1940s. The guitar's ancestors include the gittern, the vihuela, the four-course Renaissance guitar, and the five-course baroque guitar, all of which contributed to the development of the modern six-string instrument.

There are three main types of modern guitar: the classical guitar (Spanish guitar/nylon-string guitar), the steel-string acoustic guitar or electric guitar, and the Hawaiian guitar (played across the player's lap). Traditional acoustic guitars include the flat top guitar (typically with a large sound hole) or an arch top guitar, which is sometimes called a "jazz guitar". The tone of an acoustic guitar is produced by the strings' vibration, amplified by the hollow body of the guitar, which acts as a resonating chamber. The classical Spanish guitar is often played as a solo instrument using a comprehensive fingerstyle technique where each string is plucked individually by the player's fingers, as opposed to being strummed. The term "finger-picking" can also refer to a specific tradition of folk, blues, bluegrass, and country guitar playing in the United States.</think>
A typical guitar have 6 strings but there are other guitars (bass guitar) which have 4-6 strings.
The sound of the guitar is projected either acoustically, by means of a resonant chamber on the instrument, or amplified by an electronic pickup and an amplifier.
There are three main types of modern guitar, the classical guitar, the steel string acoustic guitar or electric guitar, and the Hawaiian guitar which is played across player's lap.