Ⅰ. propose “建议、提议”，是书面语，带有正式和庄严的色彩。如：
① I propose an early start. 我建议及早开始(或动身)。
② We propose that the house (should) be repaired. 我们建议对房屋进行修理。
Ⅱ. suggest “建议、提议”，但没有propose正式。如：
① I suggest a visit to the theatre. 我建议去看戏。
② I suggest that we (should) begin at once. 我建议我们立即开始。
③ He suggest going to the Summer Palace. 他建议去颐和园。