With so many children playing outside and making so much noise, he seemed unable to __________ on his homework.
| A．connect | B．concentrate |
| C．fix | D．fill |
His income is double _____ it was five years ago.
| A．that | B．which |
| C．as | D．what |
Without the air to hold some of the sun’s heat, the earth at night ____ for us to live.
| A．would be freezing cold | B．will be freezing coldly |
| C．would be frozen cold | D．can freeze coldly |
. _____ of you comes first will get the ticket.
| A．Which | B．Whichever |
| C．Who | D．Whatever |
. He hesitated for a moment before kicking the ball, otherwise he ____ a goal.
| A．had scored | B．scored |
| C．would score | D．would have scored |
He just does ______ he pleases and never thinks about anyone else.
| A．that | B．what |
| C．which | D．how |