used for emphasis with following adjective functioning as adverb. Thing that is not yet known or named.

To know the meaning of language, what someone says.

reason why something is done etc.. Reasons for which some things are done aims goals. have as intention or objective.

relating to lungs.

Most important part of something larger.

Talk or speech about a particular subject. To speak to someone to show anger or warn them.

existing or occurring before in time or order.

To any extent or degree (often used with not). Use to indicate limits or variation. any place.

any of many tiny air sacs of lungs. Tiny sacs for holding air in the lungs.

used to emphasize accuracy of figure or description.

supplied, treated, or enriched with oxygen. To add oxygen to (blood, water etc.).

Used before you explain something simply, clearly.

Two or more atoms chemically combined.

breathing at abnormally slow rate, resulting in increased amount of carbon dioxide in blood.

for short time.