Spirogyra is a large genus (about 400 species) of freshwater green algae found in shallow ponds, ditches and amongst vegetation at the edges of large lakes, generally growing free-floating.It often grows in short-lived ('ephemeral') ponds that build up during wet weather, and dry up subsquently.pirogyra is a large genus (about 400 species) of freshwater green algae found in shallow ponds, ditches and amongst vegetation at the edges of large lakes, generally growing free-floating.
General Past Tense Pronunciation Rule. An additional syllable with the -ed ending is only necessary when the last sound (not the last letter) of the base form of the verb is a /t/ or /d/; for example, wanted (two syllables), decided (three syllables), needed (two syllables), or invited (three syllables).etting Started â Adding -ed. When teaching English past tense pronunciation for regular Simple Past verbs, ESL and EFL students have to first be taught to add -ed to the end of the base form of the verb.
In English grammar, the simple past is a verb tense (the second principal part of a verb) indicating action that occurred in the past and which does not extend into the present. The simple past tense (also known as the past simple or preterite) of regular verbs is marked by the ending -d, -ed, or -t. Irregular verbs have a variety of endings. The simple past is not accompanied by helping verbs. See Examples and Observations below. Also see: Backshift and Sequence of Tenses (SOT)