https://stackblitz.com/edit/angular-material-toolbar?file=src%2Fapp%2Fapp.module.ts

app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';

import { AppComponent } from './app.component';
import { ToolbarComponent } from './toolbar.component';

import { MaterialModule } from './material.module';

@NgModule({
  imports:      [ BrowserModule, FormsModule, MaterialModule ],
  declarations: [ AppComponent, ToolbarComponent ],
  bootstrap:    [ AppComponent ]
})
export class AppModule { 
}