警棒で空をなぐりつけ、よろめいて体勢をたてなおしたガードマンは、自分に向かって突進してくる金網づくりのクズカゴを見た。

The guard's truncheon hit air. Off balance, he regained his posture to see a metal-mesh rubbish bin flying towards him.

ほとんど空なのでガソリンを入れなくてはなりません。

I need to put some gas in the car, as it's almost empty.