Your(many people) opinions are important to me = הדעות שלכם חשובות לי Your(one person) opinions are important to me = הדעות שלך חשובות לי But, as Shlomit said, it is more common to hear the word "opinion" in singular: הדעה שלך חשובה לי You made me laugh = הצחקת אותי (thankfully in hebrew we have a single word, להצחיק, which conveys that meaning of "make one laugh") you can also say גרמת לי לצחוק, but the above option would be better :)

Your opinions are important to me - if you refering to one person it is = הדעות שלך חשובות לי but you usually say : הדעה שלך חשובה לי = in singlar there is also a difference in the word: שלך when you reffering a male or female for male you pronounce: SHELCHA for female you pronounce: SHELACH