Without calling him out by name, former First Lady Michelle Obama took a subtle swipe at President Donald Trump regarding his Twitter habits.

Appearing with longtime friend and poet Elizabeth Alexander at the Obama Foundation’s inaugural youth leadership summit in Chicago, Obama offered young people some advice on tweeting.

“When you have a voice, you can’t just use it any kind of way, you know?” she said. “You don’t just say what’s on your mind. You don’t tweet every thought. Most of your first initial thoughts are not worthy of the light of day.” The audience laughed, clearly making the connection between her words and President Trump’s penchant for bypassing the mainstream media with his tweets.

Obama then clarified herself by claiming: “[I’m not] talking about anybody, in particular, I’m talking about all of us.”

Describing Twitter as a “powerful weapon that we just hand over to little kids,” Obama said it’s wrong to just “tell it like it is.” She advised kids to “think and spell it right and have good grammar.”

Obama also talked about sexual harassment.

“When we think about women, in particular, we ask them to speak up. We ask them to speak their mind. We ask them to just say no, to speak out against sexual harassment,” she said. “But if we don’t teach our young girls to speak at an early age, that doesn’t just happen. It takes practice to have a voice. You have to use it again, and again, and again before you can say, ‘No’ or ‘Stop. Don’t touch me.'”

Obama’s comments come as several higher-ups in the entertainment industry, beginning with movie mogul Harvey Weinstein, have been facing mounting allegations of sexual harassment and assault.

Parenting, gender, and the differences between raising boys and girls was another topic the former first lady tackled as she explained that her goal in raising her daughters was to make them “sturdy” enough to “exist…in a world that is dangerous to women.”

“The problem is, we love our boys and we raise our girls, you know? We raise them to be strong and sometimes we take care not to hurt men. I think we pay for that a little bit” she said. “It’s powerful to have strong men, but what does that strength mean, you know? Does it mean respect? Does it mean responsibility? Does it mean compassion? Or, are we protecting our men too much so they feel a little entitled, you know, a little self-righteous sometimes?”

She noted that her “girlfriends” keep her grounded and advised men to “talk to each other” more.

“Y’all should get you some friends,” she said, addressing the men in the audience. “Y’all need to go talk to each other about your stuff because there’s so much of it! Talk about why y’all are the way you are.”