The number of students in this university grown quickly over the past ten years．（ ）
| A． |
have |
B． |
has |
C． |
is |
More than two _____ trees are planted in our neighborhood every year．（ ）
A．hundredB．hundreds
C．hundreds ofD．hundred of
Tomorrow is our teacher's birthday and we are going to give _____ a big surprise．（ ）
A．hisB．himC．heD．himself
Jack often plays _____ piano and he wants to be a pianist when he grows up．（ ）
A．aB．anC．/D．the
Could you show me how to make a fruit salad？
______．First，you need to choose some fresh fruit of different colours．（ ）
A．It doesn't matterB．My pleasure
C．You're welcomeD．With pleasure
______ will the discussion last？
______ we reach an agreement．（ ）
A．How long； Not untilB．When； Not until
C．How long，UntilD．When，Until