①C₄H₁₀（g）+ $\frac{13}{2}$ O₂（g）═4CO₂（g）+5H₂O（l）△H=﹣2 878kJ•mol^﹣1

②C₄H₁₀（g）+ $\frac{13}{2}$ O₂（g）═4CO₂（g）+5H₂O（g）△H=﹣2 658kJ•mol^﹣1

③C₄H₁₀（g）+ $\frac{9}{2}$ O₂（g）═4CO（g）+5H₂O（l）△H=﹣1 746kJ•mol^﹣1

④C₄H₁₀（g）+ $\frac{9}{2}$ O₂（g）═4CO（g）+5H₂O（g）△H=﹣1 526kJ•mol^﹣1

由此判断，正丁烷的燃烧热是 （   ）

I always go____ (shop) with Mom on Saturday.

根据句意及首字母或汉语提示，完成下列单词。 
（1）The e____ is the biggest animal on land.
（2）The old man p____  trees in spring every year.
（3）My hobby is c____ stamps（邮票）.
（4）It's d____ to play football in the street.
（5）Will you i____your teachers to your birthday party?