我知道數學課不受歡迎。

　　I am sensible of the fact that mathematics is not a popular subject.

　　令人驚訝的是，數學課被選為他們最喜歡的科目。

　　Surprisingly, mathematics was voted their favourite subject.

　　他講數學課。

　　He gives lessons in mathematics.

　　How many subjects are you taking this year?

　　你今年修多少門課？

　　How many times do I have to tell you not to do that?

　　我得跟你說多少回不要做那種事？