试验: experiment, test, to experiment, experimental...
警官: constable, police officer...
直接: indirect ), immediate, straightforward...
一技之长: proficiency in a particular field (idiom), skill in a specialized area (idiom)...
节奏: rhythm, tempo, musical pulse, cadence, beat...
恰巧: fortunately, unexpectedly, by coincidence...
弥补: to complement, to make up for a deficiency...
过去: go over; pass by...
增: to increase, to expand, to add...
打扫: to clean, to sweep...