We generally have four people working in the shop, but at ____ periods we employ extra hands.
A、top
B、rush
C、tip
D、peak
2. In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation.
A、there
B、thick
C、thank
D、thirty
If John had entered the office ten minutes ago, he____ what we were talking about just now.