Discrete and Discreet; Complement and Compliment

Recognize two pairs of sound-alike words that often appear on tests and in academic writing.

Some advanced words are confusing not because they are rare but because they have a twin that sounds identical. Discrete means separate or distinct; in math and science, 'discrete data' comes in countable, separate values, such as the number of students in a class. Discreet means careful and tactful, especially about private matters. A memory trick: in discrete, the e's are separated by the t, just as the word means separate. Complement means something that completes or goes well with something else; in geometry, complementary angles add up to 90 degrees.

Compliment means praise. The trick: a complement completes, and both have 'ple. ' Worked example: 'The nurse was discreet about the patient's condition, and the two medications complement each other. ' The nurse is tactful; the drugs work well together. Swapping either word would change the meaning or create an error.

• 1Discrete: separate; discreet: tactful.
• 2Complement: completes; compliment: praise.
• 3Use spelling tricks to remember which is which.