Prepositions of Measure & Comparison

Expressing quantity, degree, and comparison

Sections
Introduction

1. Definition & Core Meaning

Prepositions of Measure and Comparison are used to talk about quantities, amounts, and differences between things.

What is it?
Expressing quantity, degree, and comparison

2. Use Cases

WordMeaningExample
byThe amount of change or difference"Prices rose by 10%." / "She beat him by three points."
ofA quantity of something (partitive)"A glass of water." / "Two kilos of rice." / "A piece of advice."
thanUsed in comparisons (with comparative adjectives)"She is taller than her sister." / "This is harder than I expected."
as...asUsed in equal comparisons"He is as fast as his brother."
up toA maximum limit"Up to five people can enter."
at leastA minimum"He earns at least $1,000 a month."

3. When to Use It (Time Expressions/Signals)

[!NOTE]
Use by for measured differences, of for partitive amounts, than for comparisons with comparative adjectives.

4. How to Use It (Rules)

  • by + amount → shows the degree of change or difference: increased by 5%, won by two goals
  • of + noun → shows quantity or content: a cup of tea, a lot of people
  • than always follows a comparative adjective or adverb: faster than, more beautiful than
  • as...as sandwiches the adjective for equal comparisons