汉译英:如果我知道你对我如此重要，我一定会在第一次见面对你一见钟情。

拜托专业一点如上，大意我也会翻译，谢谢

If I know you are so important to me, I will fall in love when l met you at the first time.

客气的指出楼上翻译的虽然基本上没什么问题，但是最后应该是loved YOU at first sight, 这里不可以省略宾语，否则指代不明 口语一点儿的 If I knew that you would turn out to be so important to me, I for sure would have fallen in love with you the first time I met you. 深情一点儿的 If I had known that you would mean the world to me, I would have fallen in love with you at first sight regardless of anything that might come in between. 还可以提供带有别的感情色彩的版本 如果还有问题可以找我~

If I had known you meant so much to me ,I would have met you on the spot and loved at first sight