Can children use present and past tense to learn the meanings of new words?

In this study, we are investigating whether children can use present and past tense to learn new words. Children will be familiarized with new words by watching videos of two girls, each doing an action (such as spinning a toy, stirring some water, etc.). While watching the videos, they will hear sentences in either present or past tense featuring a new word. Afterwards, children will be asked about whether they learned the new word by being asked to point to the girl on the screen that is doing the action the new word refers to. 

During the experiment, children will sit in a room with the experimenter and watch videos on a laptop. After each video, children will be prompted by the experimenter to point at the screen.