

Acho que vai chover hoje.
Sei que estás muito cansado.
A Inês diz que não pode vir.
"que" is in the lesson "Conjunctions" (Level 32), along with 13 other useful words. LinDuo has 180 topic lessons like this one, 2,380 words in total. Every word has an illustration, a transcription and pronunciation in a female and a male voice. Just 10–15 minutes a day is enough to learn them all. Free, and works offline.