ヘルプ　ms-help://MS.VSExpressCC.v80/MS.NETFramework.v20.ja/cpref8/html/M_System_Drawing_Graphics_DrawString_1_40e1d0f4.htm
の
Graphics.DrawString メソッド (String, Font, Brush, PointF)
にサンプルあるよ。
この例ではフル指定だね。

public:
void DrawStringPointF( PaintEventArgs^ e )
{
// Create string to draw.
String^ drawString = "Sample Text";

// Create font and brush.
System::Drawing::Font^ drawFont = gcnew System::Drawing::Font( "Arial",16 );
SolidBrush^ drawBrush = gcnew SolidBrush( Color::Black );

// Create point for upper-left corner of drawing.
PointF drawPoint = PointF(150.0F,150.0F);

// Draw string to screen.
e->Graphics->DrawString( drawString, drawFont, drawBrush, drawPoint );
}