________ it was done was a mystery. 这是怎样做的是一个谜。
A. Whichever
B. Whether
C. What
D. How
E. When
F. Where
查看答案
________ this happened is not clear to anyone. 这件事怎样发生的,谁也不清楚。
A. Whichever
B. Whether
C. What
D. How
E. When
F. Where
________ I spend my summer is no business of yours. 我在哪里过暑假不关你的事。
A. Whichever
B. Whether
C. What
D. How
E. When
F. Where
Listen carefully and choose the word you hear.
A. fill
B. fee
Which of the following letter or letter group can be pronounced as /r/ in English?
A. r
B. rr
C. wr
D. ll
微信支付 
支付宝支付