use ngx-translate in .ts file

Please do not use the forkJoin operator in this case. ngx-translate supports fetching multiple translations at once by passing an array of keys to the get() method like this:

translate.get(['HOME', 'MY_ACCOUNT', 'CHANGE_PASSWORD']).subscribe(translations => {
  this.pages= [
    { title: translations.HOME, component: HomePage},
    { title: translations.MY_ACCOUNT, component: MyAccountPage},
    { title: translations.CHANGE_PASSWORD, component: ChangePasswordPage}
  ];
})

Edit:

Here you can find all supported methods and their signature.