The waiting room was empty when I first got there, but it started getting crowded later.
There was hardly anyone in the waiting room at first, but more people started to come in later.
①The waiting room was empty when I first got there, but it started getting crowded later.
「最初に待合室に着いた時は空いていたけれど、後から混んで来た。」
The waiting room→待合室
empty→誰も居ない、空の状態
when I first got there→最初にそこに(待合室)着いた時
it started getting crowded→混み始めて来た
later→後から
②There was hardly anyone in the waiting room at first, but more people started to come in later.
「初めは待合室に殆ど誰もいなかったけれど、後から人が増えて来た。」
There was hardly anyone in the waiting room→待合室に殆ど誰もいなかった
more people started to come in later→後から人が増えて来た
少しでもお役に立てれば幸いです。