(1) Answer: B. to
Explanation: "Always maintain a queue while waiting to board a bus."

(2) Answer: B. sit
Explanation: "Once you are inside the bus, sit and hold firmly on the handrail if you are standing."

(3) Answer: D. board
Explanation: "Never try to board an overcrowded bus."

(4) Answer: C. to shout
Explanation: "Avoid to shout inside of a bus because your high-pitched voice may distract the driver."

(5) Answer: D. street
Explanation: "It could lead to a major street accident."

Answer: C. should learn two foreign languages
Explanation: The passage suggests that learning two foreign languages is beneficial for children.

Answer: A. experts
Explanation: The word "they" in line 1 refers to the "experts" who think it's a good idea.

Answer: C. two languages which are different from one another
Explanation: The passage suggests learning languages that are distinct from each other.

Answer: B. Children should start to learn foreign languages from the age of about six.
Explanation: This is stated in the passage, so it’s not "NOT TRUE."