あとで図書館に行きましょうか。 Ato de toshokan ni ikimashou ka. 'Shall we go to the library later?'
降りる oriru 'to get off'
渡る wataru 'to cross'
休む yasumu 'to rest'
図書館 toshokan 'library'
ちょっと chotto is often used in polite commands or let's sentences, as here. It often has an apologetic feeling.