Learn the grammar rules and uses of the present perfect tense with clear examples. Discover common mistakes and how to avoid them. Perfect for B1–B2 English learners.

Learn how to use gerunds in English, including in the passive voice, and the difference between gerunds and present participles.

Learn the differences between "should" and "should have" in English, including everyday and formal uses.

Recommended level: Advanced Quick Reference In most cases, affect is used as a verb and effect is used as a noun. (Ex: "The decision...