问几道英语选择题( )2.Would you please say that again I didn't FOLLOW

问几道英语选择题
( )2.Would you please say that again I didn't FOLLOW you .The underlined part means _________ .
A.know B.learn C.hear D.catach
理由：____________________
（C）What do you mean _____ acting the medicine .
A.in B.on C.by D.with
理由：____________
(A)-What will you have ____ dinner today
-Sorry.I have no ideas.,
A.for B.of C.in D.at
理由：___________
我只知道2道题的答案,帮我看看吧,顺便说一下理由!