Translate the following sentence into English.
从高中时起，他就梦想成为一名医生。现在，他正努力实现自己的梦想。
【正确答案】：
HE HAS DREAMED OF BECOMING A DOCTOR SINCE HIGH SCHOOL AND IS NOW TRYING TO MAKE HIS DREAM COME TRUE.
【题目解析】：
考点：dream of doing sth.：梦想做某事；try to do sth.：努力做某事；come true：实现
句子结构：根据“从高中时起”判断是现在完成时态。“现在”和“正”表明第二句话是现在进行时态。