IPA: /ˈstrɛŋkθən/
KK: /ˈstrɛŋkθən/
To become more powerful or more effective.
The team worked hard to strengthen their skills before the competition.
Past: strengthened
Past Participle: strengthened
To make something stronger or more powerful.
The coach worked hard to strengthen the team's skills before the big game.
Past: strengthened
Past Participle: strengthened
Strengthen → It is formed from "strength" (from Old English *strength*, meaning power or force) and "-en" (a suffix used to form verbs indicating to cause to be or to become). The word "strengthen" means to cause to become stronger or to increase in power.
Think of the word 'strength' which means power, and remember that 'strengthen' means to make something more powerful.