"I miss you" is the English translation for "我想你了". This phrase is a simple way to express that you are thinking of someone and wishing they were present with you. It can be used in a variety of contexts, such as when a friend leaves for a while or when a loved one passes away. The tone can vary depending on the situation, but it generally conveys a sense of longing and affection. If you want to add more detail to your message, you could say "I miss you so much today" or "I've been thinking about you all day".
