The drivers on the highway have to stop because the thick fog makes ____difficult to see. A,them B,it C,that D,this
Li Na ____________ her husband’s significant contribution in her development on the WTA Tour.
It makes great sense to check and ____________ the brakes(刹车)regularly.
Right now you may not know how relevant English learning is _________ your future.
They ___________ with the aim of becoming number one in the league.
I called you up last night but I couldn’t _____________.