Irregular period is the same as a period. Irregular just means no set pattern, for example your period might come 1 week after you finished your first one or it might come after 3months or so.
meter
It is irregular.
It is an irregular polygon.
Not necessarily. A rhombus is an equilateral quadrilateral but does not have a line of symmetry. An irregular octagon does not, either.
It is irregular
"Think" is an irregular verb. In the past tense, it changes to "thought" instead of following the regular -ed pattern.
The verb "blew" is an irregular verb. It does not follow the standard pattern of adding "-ed" to form its past tense.
"Began" is an irregular verb. Its past tense form does not follow the usual pattern of adding "-ed" to the base form of the verb.
An irregular verb, for instance: TO BE, CAN, etc.
irregular with a pattern
No, the word "women" is not irregular. It follows the typical pattern of pluralizing nouns ending in "-man" by changing the ending to "-men."
"Built" is an irregular verb. Regular verbs form their past tense by adding "-ed" to the base form, while irregular verbs have unique past tense forms that do not follow this pattern.
Yes, some are big some are small.
Yes, "buy" is an irregular verb. The past tense of "buy" is "bought," which does not follow the typical -ed pattern of regular verbs.
In English, there are only two verbs that are irregular in the present tense: to be (am/are/is/are/are/are) to have (have/have/*has*/have/have/have) The modal verbs follow a different pattern than regular verbs but are not technically "irregular": will shall must etc.
"Have" is an irregular verb in English. This means that its past tense form ("had") and past participle form ("had") do not follow the typical pattern of verb conjugation.