变胖的句子怎么说英语

To say "I have gained weight" in Engpsh, you can say "I have gotten heavier" or "I have gained some pounds." You can also say "I have put on weight" or "I have become heavier." If you want to be more specific, you can say "I have gained X pounds" or "I have put on X pounds," where X is the amount of weight you have gained.