It’s a eucalyptus. We use “a” or “an” based on the sound, not the spelling, made by the initial letter of the word that follows.

It’s a euphemism. The rule for using “a” or “an” is based on pronunciation, not spelling. Since “euphemism” starts with a consonant sound ("you" sound), we say “a euphemism”.

We typically use the article “the” to introduce a range of leisure activities and forms of entertainment (e.g., “to the beach”, “to the mountains”, “to the movies”, “to the disco”, “to the opera”, etc.).

When visiting an area that is next to the sea, we commonly use the expression “go to the coast” (with the article “the”).

We use the expression “go to sea” (without “the”) to say that someone becomes a sailor or embarks on a voyage.

We say “go to the beach” (not “go to beach”). Follow the same strategy with other related expressions, such as “walk along the beach”.

In normal conversations, we commonly use the expressions “do the dishes”, “do the laundry”, or “do the housework”. We can omit the article to put the emphasis on the activity rather than the items to be washed or cleaned.

In everyday English, we use the expression “do the cleaning” (with the article “the”) to speak about the process of making a house or an office clean.

When referring to the task of making clothes flat and smooth, we typically put the definite article “the” before “ironing”.