nhớ tick nha

\(+ Chùm sáng song song: bao gồm các tia sáng giao nhau trên đường truyền của chúng.+ Chùm sáng hội tụ: gồm các tia sáng không giao nhau trên đường truyền của chúng.+ Chùm sáng phân kì: gồm các tia sáng loe rộng ra trên đường truyền của chúng.\)

\(Tiếng Anh Spring has returned to my hometown. Spring begins in January and ends in March. Spring comes to nature as if wearing new colors, tree branches begin to sprout. Spring has come and countless flowers are blooming all over the streets. In my garden, thousands of flowers bloom each other. The birds also sang songs to welcome the coming of spring, contributing to the bustling and exciting spring atmosphere. I love spring very much because it is associated with the nation's Tet holiday.\)

\(Cuc Phuong National Park is located in Nho Quan District, Ninh Binh Province. It became a national park in 1962. Its area is about 222 sq. km. It was Vietnam's first national park and it is still the largest. This park has a rich diversity of plants and animals. Many species in the Vietnam Red Book of Endangered Species are found here. The park has the Endangered Primate Rescue Centre and Turtle Conservation Centre, which help to save a lot of species from extinction.\)