Can, may are often confused in use.
Calm vs Compose vs Quiet vs Quieten vs Still vs Lull vs Soothe vs Settle vs Tranquilize
Calm, compose, quiet, quieten, still, lull, soothe, settle, tranquilize are comparable when they relate to persons and their feelings and moods and mean essentially to bring to an end or relieve from whatever distresses, agitates, or disturbs.
Calm vs Tranquil vs Serene vs Placid vs Peaceful vs Halcyon
Calm, tranquil, serene, placid, peaceful, halcyon mean quiet and free from all that disturbs or excites.
Calculate vs Compute vs Estimate vs Reckon
calculate, compute, estimate, reckon mean to determine something (as cost, speed, or quantity) by mathematical and especially arithmetical processes.
Cad vs Bounder vs Rotter
Cad, bounder, rotter mean one who shows himself to be no gentleman. Usually they are somewhat vague terms of contempt for bad behavior or manners.
By vs Through vs With
By, through, with are comparable as prepositions followed by a word or phrase naming the agent, means, or instrument.
Buy vs Purchase
Buy, purchase mean to acquire something for money or an equivalent.
Buttress vs Pier vs Abutment
Buttress, pier, abutment are architectural terms for auxiliary structures designed to serve as a prop, shore, or support for a wall (as of a building).
Busy vs Industrious vs Diligent vs Assiduous vs Sedulous
Busy, industrious, diligent, assiduous, sedulous mean actively engaged or occupied in work or in accomplishing a purpose or intention.
Back to the drawing-board vs Back to the salt mines
back to the drawing-board—dealing with the same matter again (because smth. has gone wrong):
Business vs Commerce vs Trade vs Industry vs Traffic
Business, commerce, trade, industry, traffic are comparable chiefly when they denote one of the forms or branches of human endeavor which have for their objective the supplying of commodities.
Bridal vs Bridle
Bridal refers to a marriage ceremony.