The little problems ____ we meet in our daily lives may be inspirations for great inventions.
A. that
B. as
C. where
D. when
查看答案
My eldest son, ____ work takes him all over the world, is in New York at the moment.
A. that
B. his
C. whose
D. who
Those passengers will wait here____ the bus arrives.
A. until
B. because
C. though
D. as
Has the meeting begun yet? --Not yet, we have to wait____ everyone is here.
A. where
B. until
C. or
D. however
You will fall behind others____ you work hard.
A. if
B. unless
C. even though
D. since
微信支付 
支付宝支付