we shouldn't spit in public or litter things.

we shouldn't spit in public or litter things.
we shouldn't spit in public or litter things.

we shouldn't spit in public or litter things.
我们不应该在公共场合随地吐痰,乱丢垃圾!

我们不应该在公共场合随意吐痰或乱扔垃圾

我们不应该在公共环境中乱丢垃圾，随地吐痰！

我们不应该在公共场所吐痰或者是乱丢垃圾。