be all smiles 眉开眼笑

眉开眼笑，汉语成语，意思是眉头舒展，眼含笑意。形容高兴愉快的样子。可以翻译为“be all smiles，be radiant with smiles或beam with joy”等。

例句：

孩子们收到礼物时眉开眼笑。

The children were all smiles when they received their presents.