_______man must fear when travelling in space is radiation from the sun.
| A． Which | B． How | C． What | D． That |
He was wild with joy when he ______ a solution to the difficult problem.
| A．made up with | B．put up with | C．came up with | D．kept up with |
______ of the parents has confirmed it was their child’s fault to be late for class, saying the school bus came later than usual.
| A．Both | B．Either | C．None | D．Neither |
______ he explained it to me did I make sense of what he said.
| A．Hardly had | B．Not until | C．Shortly after | D．No sooner |
It sounded like something was wrong with the car’s engine then, ______ they would have carried on their journey.
| A．otherwise | B．therefore | C．meanwhile | D．besides |
---There is still some doubt ______ he is innocent.
---That’s why he was accused ______ the crime.
| A．that; with | B．whether, of | C．that, of | D．whether, with |