他投票反对这项提案。

He voted ___against the proposal.

他把梯子靠在树上准备摘苹果。

He placed the ladder ___against the tree to pick apples.

她买了些罐头食品以防停电。

She bought some canned food ___in case of possible power outages.

他撞到了墙上，肩膀有点疼。

He bumped ___against the wall and his shoulder hurt a little.

红色的花朵在绿叶的衬托下格外醒目。

The red flowers look striking ___against the green leaves.