When _______________ comes to saving energy, big changes start with small steps, like turning off the lights.
| A．that | B．this | C．it | D．one |
They can find whatever they need in the supermarket, ______ is always busy on Sundays.
| A．which | B．when | C．where | D．who |
【原创】According to RocketNews24, more than a few others expressed hope that they too, could find a gem _________ they chomp down on the seafood snack, losing a tooth or two notwithstanding.
| A．when | B．the next time |
| C．next time | D．the instant |
【原创】Picatoo has launched ______ service which transforms Instagram photos into ______ temporary inkings that can be worn wherever you like on your body.
| A．the; the | B．a; a | C．the; a | D．a; / |
Mother often reminds me that the best thing one can do ______ it is raining is to let it rain.
| A．unless | B．when | C．even if | D．in case |
— Have you got the sleeping bag needed for the camping this weekend?
— Yes, I ______ it almost the moment I heard the news.
| A．bought | B．had bought |
| C．have bought | D．would buy |