I went shopping last Sunday,I was/am very happy.was和is哪个正确?或

was.时态前后一致
再问： 但是如果我想表达到现在都很高兴呢？
再答： 如果不动原句，就比较麻烦，但日常口语里会经常如此 I went shopping last Sunday,I was very happy. And I am still very happy now. 照你的意思表达： I went shopping last Sunday and I've been very happy since then.