ester gum

例句：

1. 1. The engineer used ester gum to seal the cracks in the concrete.
   工程师使用酯胶来密封混凝土中的裂缝。
2. 2. The construction workers applied ester gum to the wood to protect it from moisture.
   建筑工人在木材上涂抹酯胶以保护它免受湿气侵蚀。
3. 3.The adhesive was made from natural oils extracted from plants and contains no harmful chemicals.
   这种粘合剂由从植物中提取的自然油制成，不含有害化学物质。