More about verbs
The past Participle (action past) is shown with the same arrow on top of the verb but pointed to the left because the action is past.
The Gerund, as it is an action that is coming from the past but going into the future, something that is happening, is made of both tenses, future and past, se we put both dots on top of the verb:
Let's see these two sentences:
In the first sentence we are using the Gerund just as we have seen it; but in the second sentence, although it expreses an action (to grow) that continues into the future, the said word Growing is acting more like an adjective attached to the noun Children. This is why we put the underarrow in the direction of the noun Children. See Section 4 for basic verb tenses.