0 from or referring to the period of time between about 66 and 23 million years ago, in which many insects, mammals, and birds appeared: --
1 the period of time between about 66 and 23 million years ago, in which many insects, mammals, and birds appeared: --
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Vi kan slutföra det steg för steg hur lång vägen än är och den kan inte slutföras hur kort vägen än är om du inte ens markerar ditt fotavtryck.